The present invention relates to universal joints and more particularly, to a shield for a universal joint.
Universal joints have found wide application to couple rotary shafts that have an angular misalignment. For example, a double universal joint is often used to couple the power take-off shaft of a mobile prime mover such as a tractor to the power input shaft of an attached implement. Since the implement can pivot relative to the prime mover, the drive line from the prime mover to the implement must also be pivotal. The universal point provides such an articulated coupling between the power take-off and power input shafts.
The prior art has recognized the dangers of exposed universal joints in drive lines of the type described. Shields for universal joints are therefore also well known. Prior art shields are usually provided in two halves. One half of the shield is usually fixed or journaled upon a rotating member of the drive line and the other half of the shield is stationary, being fixed to either the prime mover or to the implement. Due to the limited amount of space that is available for the shield on the prime mover or the implement, the rotating shield often interferes with the stationary shield when there is a wide angle between the drive and driven shafts. To avoid this interference, users commonly remove the shield on the prime mover or implement. Of course, this exposes about half of the universal joint thereby creating a dangerous condition.
Some prior art shields are mounted to rotating members of the drive line and fully enclose the universal joint. However, these fully enclosed shields are only capable of relatively small bending angles. Therefore, a need exists for a fully enclosed shield for a universal joint which is capable of wide bending angles.